Electric welding apparatus



l July l', 1947. G. GILLlvER ELECTRIC WELDING APPARATUS Filed March 26, 1945 2 Sheets-Sheet l A itorney July 1, 1947. G|| l 1vE -,R i 2,423,096

' 'ELECTRIC WELDING APPARATUS .Filed March 26,l 1945 2 sneets-sheet 2 Inventor s: vHaz. W

- Attorne! Patented July 1, 1947 ELECTRIC WELDING APPARATUS Gilbert Gilliver, London, England, assignor to Standard Telephones and Cables Limited, London, England, a British company Application March 26, 1945, Serial No. 584,799 In Great Britain April 21, 1944 6 Claims.

This invention relates to electric welding apparatus for joining wires or the like, and is particularly applicable for use with the condenser discharge welding apparatus described in the specification of my co-pending U. application, Serial No. 554,368, iiled September 16, 19%4.

The invention provides a tool for the electric fuse welding of conductors comprising means for clamping the conductors with their ends in a fixed position with respect to a welding electrode, a shutter normally interposed between the conductors and the electrode, and means for advancing the electrode into contact with the said ends, the last-mentioned means being adapted also to cause the withdrawal of the shutter out oi the path of the electrode.

Stated in another Way, the invention provides a tool for the electric fuse welding of conductors comprising clamping means adapted when operated to clamp the conductors with their ends 0D'- posite a welding electrode, a, gauging shutter interposed between the conductors and the elec trode and adapted to locate the said ends at a specified distance from the said electrode, means for advancing the electrode into contact with the said ends, the last mentioned means being also adapted rst to release the shutter to permit it to be withdrawn from the path of the electrode by means provided therefor, and means adapted on the release of the clamping means to restore the shutter to the interposed position.

More specifically the invention also provides a welding tool designed for attachment to the welding equipment and comprises lever operated jaws for clamping the wires to be welded, a carbon welding electrode mounted on a spring controlled plunger and adapted to be moved into contact with the ends of the wires, a shutter device associated with the jaws and normally interposed between the wires and the electrode and means associated with the plunger operated electrode for releasing the shutter and allowing the electrode to make contact with the wires in a predetermined position.

More particularly when designed for use with the condenser discharge apparatus above referred to the welding tool comprises an operating lever arranged to open and close two copper jaws which clamp the wires to ,be welded, and a carbon electrede holder iitted with a restoring spring and contacts which charge a condenser in their un operated position, and discharge the condenser through the carbon electrode, the wires to be welded, and the copper jaws, when the push but'- 2 .ton is pressed forward to bring the electrode into contact with the wires to be fused.

The lever also operates a movable shutter which is locked in position behind the copper vice jaws when the lever is in the vertical position, which shutter acts as a gauging stop for the wires inserted in the aperture and ensures that they are located in the correct position for the carbon electrode to fuse weld the Wires and form a satisfactory bead thereon.

The advance of the push button first releases the shutter stop by means of an insulating stud which releases the catch holding the shutter and the shutter is Withdrawn by a spring out of the way of the advancing carbon electrode.

After welding, the lever is restored, the wires removed and this operation restores the shutter to its gauging position.

The invention will be explained with reference to the accompanying drawings of which Figs. 1 and 2 show respectivelj7 front and side views of an example of a welding tool according to the invention adapted for use with the condenser discharge fuse welding equipment described in the Y above mentioned specication.

The tool comprises a built-up box of Bakelite panels and side pieces I carrying two copper busbars 2 and 3 on the underside of the top panel which have circular ends provided to enter circular sockets on the fuse welding equipment. One of these bus-bars 2 is connected by screws and nuts to a metal bracket 4 which carries a iixed metal vice jaw 5, a movable metal vice jaw 5, an operating handle 1, a cam 8 controlling the movement of a slide 9 and an extension I0 which carries the moving vice jaw E, and which is controlled by the spring Ill The cam 8, the slide 9 and the extension I9 are mounted between the bracket 4 and a front plate I2 in such a manner that when the handle 1 is in the vertical position, the operating vice jaws 5 and 6 have a suitable opening for the insertion of the wires to be welded.

The handle 'I is pivoted on the back of the bracket 4 and carries a roller I3 which when the handle I is restored after welding to the vertical position shown, depresses the gauging shutter I4 so that it lies behind the welding aperture and is retained in position by the catch I5.

The wires are inserted in the aperture until they make contact with the shutter I4 and the handle 'l is then depressed to a 90 position; this clamps the wires iirmly between the vice jaws 5 and 6.

The other bus-bar 3 is connected to a copper 3 block I 6, which is drilled to take the push button stem or plunger I'l. A plate I 8 mounted on the front of the push button stem Il carries the carbon electrode I9 mounted in a spring holder 2B, a pin of insulating material 2|, and a contact 22.

A piece, of copper braid 23 connected between the copper block I5 and the contact plate I8, ensures a good electrical connection with the electrode I9.

The push button stem Il has a head 24 under which is a spiral spring 25 which restores it to its non-operated position. Thec'ontact 2v2 carried on the plate I8 engages a contact 26 mounted on a spring 21 carried on top of the box l' and is intended to be connected eXib'ly' to. a looseplug (not shown) which is inserted in a socket on the welding equipment when the tool is fixed for use.

A cover 28 completely encloses the inner Working partsv of the tool, prevents hot fragments from iiying out of the tool and shields the welding4 flash from the operators eyes.

The bus-bars 2' and 3 arey intended to be connected' to .the two terminals of a source of weldingcurrent which may, for example, be a charged welding -condenser such as is described in the above quotedspeciication.. The contact 26 is in that case connected to one terminal of the charging source for the welding condenser, and therefore maintainsv the condenserv charged, since the contact 222i which it engages in the unoperated position of the plunger l3` i's connectedthrough the block ll tothe bus-bar 3'. Asl soonv as the plunger IJ isV operated, the. contacts 22f and 26 are opened, thus disconnecting the condenser from the charging source, so that it is ready to fusewfeld thewires to be joined. The details of this varrangement can be, obtained from the spacincatien-.mentioned` As here shown, the condenser discharge and charging circuit arrangement includesfa transformer 3B. having its primary energized from: a suitabley source and its secondary connected by an adjustable tap to` a rectifier bridge network having its positive terminalv conneet'ed through thef'condensers 31 .to the bus bar or terminal 3 to-normally complete the charging circuit throughthe contacts 2:2 and the latter or which is connected: to: the negative pole of the rectie'r bridge: The. terminal. or bus-bar 2 is likewise connectedxas shown to the: positive terminal `ithe rectifier bridge for completion of the welding circuit from the' condensers through the wires to `l be joined when the: carbon electrode is advanced, the return circuit then being through the bus bar 3v tothe negative terminal of the condenser.

The wireshaving beenv clamped as previously described, the push button head 24 is pressed, opening the contacts 22 and 2S above referred to: The insulating pin 2| depresses the catch |5 and releases the shutter I4 which is lifted by a spring' 29;

Ony further advancing the press button head 24 the carbon electrode I94 makes contact With the wires and fuse welds them with a beadl by dischargingthrough them the welding condenser in the manner described in the above quoted sp'ecication.

On-release; the push button head' 24 is restored bythe spring 25, and the'contacts 22 and 26'engage again, thus recharging the condenser. The handle 'l is then restored to `the vertical position, releasing the welded wires and restoring the shutter i4 to its gauging position ready for the next operation.

It will be understood that .the invention is not limited to the precise details of construction described above, but is capable of various modifications. Also although reference has been made to the joiningk or"` wires itV will be' appreciated that this expression is intended to include the joining of wires or strips etc. to terminal tags or other devices.

What is claimed is:

l. A tool for the electric fuse welding of conductors comprising means for clamping the conductors with their ends in a fixed position With respect to a welding electrode, a shutter normally interposed between the conductors and the electrode, and independently actuated means for advancing the electrode into contact with the said ends, the last-mentioned means being adapted also to cause the withdrawal of the shutter out of the path of the electrode.

2. A tool. for the electric fuse Welding of con.- ductors comprising clamping means adapted when operated to clamp the conductors with their ends opposite a Welding electrode, a gauging shutter interposed between the conductors and the electrode and adapted to locate the said ends at a specified distance from the said electrode, independently actuated means for advancing the electrode into contact withr the said ends, the last mentioned meanslbeing also adapted rst to release the shutter to permit it to be Withdrawn from the path of the electrode by means provided therefor, and means adapted on the release of the clamping means to restore the shutter to the interposed positions.

3. A tool for the electric fuse'welding of conductors comprising lever operated' jaws` for clamping the conductors to be welded, a carbon welding electrode mounted on a spring-contro-lledV plunger and adapted upon independent actuation to be moved into contact with the ends of the conductors, a shutter device associated with the jaws and normally interposed between the conductors and the electrode, and means associated with the plunger for releasing the shutter andk allowing the electrode to make contact with the conductors in a predetermined. position.

4. A tool for the electric fuse welding oi conductors comprising a lever adapted on operation t'o close two copper jaws for clamping the conductors to be welded, a carbon electrode secured in a, holder mounted on a spring-controlled push button device for advancing the electrode into contact with the ends of the conductors, a shutter device associated with the jaws and normally interposed between the conductors and the electrode, means associated with the push button device for causing the withdrawal of the shutter device from the path of the electrode, and circuit means connected with the push button device to charge a welding condenser in the unoperated position thereof, and for discharging the said condenser through the conductors, jaws, and electrode When the electrode makes Contact with the conductors.

5. A tool according to claim 4 comprising a spring adapted to urge the shutter out of' the path of the electrode, a catch adapted to hold the shutter in position against the action of the spring, and an insulating pin associated with the push button for operating the catch to release the'shutter after the push button has advanced a short distance fromitsunoperatedposition.

ductors, thereby fuse welding the said conductors together.

GILBERT GILLIVER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 10 Number Name Date 1,897,606 Cole et a1 Feb. 14, 1933 2,294,388 Dawson Sept. 1, 1942 

